1. Field of the Invention
The present invention is directed antibodies specific to multiple beta blockers, as well as immunogens used to produce the antibodies, and immunoassay kits and methods for using the antibodies.
2. Description of Related Art
Beta blockers are a class of commonly-prescribed drugs used in the management of individuals with high blood pressure, congestive heart failure, abnormal heart rhythms and chest pain. Presently, more than ten different beta blockers are available, all by prescription. Currently available beta blockers include Atenolol (4-[2-Hydroxy-3-[(1-methylethyl)amino]propoxy]benzeneacetamide), Metoprolol (1-[4-(2-Methoxyethyl)phenoxy]-3-[(1-methylethyl)amino]-2-propanol), Bisoprolol (1-[4-[[2-(1-Methylethoxy)ethoxy]-methyl]phenoxy]-3-[(1-methylethyl)amino]-2-propanol), Acebutolol N-[3-Acetyl-4-[2-hydroxy-3-[(1-methylethyl)amino]propoxy]phenyl]butanamide), Esmolol (4-[2-Hydroxy-3-[(1-methylethyl)amino]propoxy]benzenepropanoic acid methyl ester), Propranolol (1-[(1-Methylethyl)amino]-3-(1-napthalenyloxy)-2-propanol), Pindolol (1-(1H-Indol-4-yloxy)-3-[(1-methylethyl)amino]-2-propanol), Timolol ((S)-1-[(1,1-Dimethylethyl)amino]-3-[[4-(4-morpholinyl)-1,2,5-thiadiazol-3-yl]oxy]-2-propanol) and Nadolol (5-[3-[(1,1, -Dimethylethyl)amino]-2-hyroxypropoxy]-1,2,3,4-tetrahydro-2,3-naphthalenediol). According to RxList.com, the following four beta blockers were the most prescribed beta blockers in 2002: Atenolol, Metoprolol, Bisoprolol and Propranolol. These drugs were ranked 3rd, 19th, 139th and 140th, respectively, in the top 200 prescriptions for 2002 based on the number of US prescriptions dispensed.
Detection of beta blockers in physiological fluids is often desirable. For example, insurance companies often wish to test for beta blockers as part of their screening processes. Thus, a method for detecting beta blockers in physiological fluids is needed.
Various techniques have been employed to detect drugs in physiological samples, including gas-liquid chromatography, mass spectroscopy, fluorometry and immunoassays. Immunoassays are widely used to detect drugs in physiological samples because such assays are inexpensive and can be performed rapidly. Immunoassays detect chemical substances in a sample using highly specific binding between an antibody and the target chemical. Thus, in order to have the desired specificity, immunoassays are normally specific for a single drug. It is difficult to develop an antibody that will bind to a class of drugs, yet not bind to other drugs and substances that may be present in a sample.
Currently, no known immunoassay detects multiple beta blockers that may exist in a sample. Rather, in commercially available beta blocker immunoassays, the antibody used in the test is specific to a single beta blocker. For example, various antibodies are specific to Propranolol, but unreactive with other beta blockers. In addition, for a majority of beta blockers, there is currently no immunoassay available. As a result, the most commonly prescribed beta blockers, such as Atenolol and Metoprolol, are not detectable by any currently available immunoassay. Thus, a need remains for a test that can detect a variety of the commonly-available beta blockers in a single immunoassay.